Gas-fired pottery kiln



A. MCD. DUCKHAIVI;

@As msn POTTERY KlLN.

APPLICATION FILED DEC.29, 1921.

aented July E87 w22,

2 SHEETS-SHEET 1.

` ggg A A. MCD. DUCKHAN.

GAS FIRED POTTERY KILN. APPLICATloN FILED DEC,29.1921.

Patented uy i8, i922.

2 SHEETS-SHEET 2.

A 'I may @ci e, i am *l l l f e 'si z' i` l i i? v i ilhiiliaar alfrasdiarias@ Altri-run. ivrcnoneann DUGKHAM, or Lennon, ENGLAND.

GAS-Frama rofrfrnnsz mijn.

gglg. Specification of Letters Patent. Patgmflk July 1S g22 Applicationled December 29, 1921. Serial No. "25,723.

Be it known thatl, Anm-iur. MGDOUGALL Doom-rami, a subject of the Kingof Great Britain, residing in London, England, have invented certain newand useful lmprovements in Gas-Fired Pottery Kilns (for which l havemade application for patent in Great Britain, dated @otober 5, 1920,Serial No. 28,248), of which the following is a specification. n Inkilns for burning argillaceous ware such as bricks, pottery and the.like, heat is generally supplied to the kiln at one or more points inthe kiln chamber, the heat being obtained by the direct combustion ofsolid fuel in gratesk forming part of the kiln chamber itself, or by thecombustion of gases supplied by a central generator. In some cases hotairis supplied for completing the combustion.` The combustion Zone isusually a small chamber of brickwork known as a bag, forming part of theconstruction of the kiln. The disadvantages of this system of heatingare: (l) That the brickwork of the kiln proper is subjected to thedirectand intense heat ot the combustion in the bag, with consequentheavy eX-` penses for maintenance. (2) The bags being isolated indifferent parts of the kiln, the heating is inclined to be localizedabout that portion ofthe kiln. (3) The heating usually being in adownward direction, the materials are notconsistently burnt throughout,the upper portions of the material in the kiln being more highly heatedthan the lower. y

By this invention these disadvantages are overcome by providing one ormore bags or chambers for combustion independent of the kiln brickworkproper which dividesuthe kiln into two or more parts and so that theheating gases escaping from the bag traverse the material contained inthe kiln between the bag and the walls of the kiln, or between the-bags,the gases escaping through iiues suitably formed by the stacking of thegoods in a suitable manner. The bag is constructed ot suitable brickworkand preferably formed into separate chambers throughout its length. kThegases for heating the kiln may be supplied to the bag by means of a flueor iues preferably situated beneath the bag and` may enter the bagthrough nostrils in its floor. Air for the combustion may be suppliedthrough similar flues and nostrils, and combustion occurs in-the chamberorchambers of the bag. Da'inpers are providedv for the proper regulationof the combustion. rlhe top of the bag is preferably closed but portsmay be left in the top covering, in order that any desired amount ofheat can be allowed'to pass to the top of the kiln. The sides of the bagare conveniently formed of chequered brickwork, the openings in thesides being so formed that they can be easily regulated between eachcharging of the kiln so as to give the desired intensity of heating inthe different horizontal'zones of the kiln.

The material to be burned isl placed in the kiln, on each side of thecentral bag between it and the sides of the kiln, and, if desired, alsokabove the top level of the bag. Since combustion occurs inside the bagand the latter does not form any part of thekiln, the briekwork of thelatter is not damaged in rany way by the direct combustion of the gases.Further, the bag can be repaired or entirely renewed without disturbingthe brickwork of the kiln proper.

Another advantage of this system of heating is that complete combustionmay be obtained in the chambers of the bag itself, and in the gasespassing through the comparatively small chequered openings; this meansthat the gases passing forward to heat the material inthe kiln will beeven in 'temperature. Y

The heating gases on leaving the bag pass for the most partltransversely through the material in the kiln tothe sides of the kiln,and may then pass downwards through ports in the tioor, returning to thecentre under the floor thus heating the latter, to the collecting fluethrough which they pass to the chimney, to an adjoining kiln for thepreliminary heating thereof or to any other device for using the heatstill remaining in the gases.

ln the accompanying drawings Fig. l is a longitudinal vertical sectionand Fig. 2 is a transverse section on line 2 2 of Fig. l of a kilnconstructed in accordance with the invention. l

In the kiln a is built the gas bag Z) eX- tending from end to end of thekiln along its middle. Heating gas from the producer c passes along theflue CZ and enters the gas bag through nostrils c in its door. Air forcombustion enters through inclined nostrils f, one on each side of eachgas nostril c, from tlues g which extend in serpentine form beneath thekiln between similarly serpentine flues 7L which convey products ofcombustion as presently explained. y

The products of combustion escape from the gas bag through openings z'in its sides and openings c in its cover Z. Hence they traveltransversely through the argillaceous material placed in the kilnchamber m and down the sides of the kiln, Where passages have been leftin piling up the material, into flues n which communicate by ports owith the aforesaid fines It. From the latter they pass to the chimney.

Having thus described the nature of the said invention and the bestmeans I know of carrying the same into practical effect, I claim i l. Agas fired rectangular kiln for burning argillaceous Ware, a gas bagtherein constructed independently of the brickwork of the kiln proper,said gas bag dividing the kiln into a plurality of compartments, saidbag having constricted apertures in the sides and top whereby heatinggases escaping from the bag are evenly distributed and traverse the Warecontained in the kilnv between the bag and the Walls of the kiln, thebulk of the gas passing through the ware in a horizontal direction.

2. A gas iired kiln for burning argillaceous Ware having a gas bagconstructed independently of the brickwork of the kiln itself and alongthe middle of the kiln, said gas bag being so formed that combustion ofthe gases takes place in the bag `and is substantially completebeforethe heating gases leave the bag and whereby the products ofcombustion do not impinge directly on the brickivork of the kiln.

3. The construction of the gas bag referred to in claim l, with acovered top and with constricted openings in its sides and top.

4:, A gas iired kiln for burning pottery,

bricks or the like having a gas bag constructed independently of thebrickwork of the kiln itself and along the middle of the kiln said gasbag being so formed that conr bustion of the gases takes place in thebag and is substantially complete before `the heating gases leave thebag and that the products of combustion do not impinge directly on thebrickwork lof the kiln, and a covered tcp with constricted openings inits sides and top.

5. A `gas Iired kiln for argillaceous Ware comprising within the kilnstructure, a gas bag sub-diviiling the kiln chamber externally to thesaid gas bag into compartments and constructed independently of thebrick* Work of the kiln itself, and flue openings in the Hoor of thekiln chamber adjacent to the sides thereof, for the purpose set forth.

6. A gas fired kiln for burning argillaceous ware comprising Wi thin thekiln chamber, a gas bag constructed independently of the brickivork ofthe kiln itself and eX- tending along the middle line of the kilnchamber and from end to end thereof, and flue openings in the lloor ofthe kiln chamber adjacent to the sides thereof, for the purpose setforth.

7. A gas ,fired kiln for burning argillaceous ware, comprising Withinthe kiln chamber, a gas bag constructed independentlyof the brickwork ofthe kiln itself and extending along the middle line of the kiln chamberand from end to end thereof, a cover to the top vof the said gas bag,openings in the s aid cover and in the sides of the bag, the saidopenings being adapted to be varied by insertion `or removal of bricksand flue openings in the floor of the kiln chamber adjacent to the sidesthereof, for the purpose set forth.

In' testimonyv whereof I have signed my name to this speciiication. A

ARTHUR MCDOUGALL DUCKHAM.

